/sci/ - Science & Math

http://www.sciencedaily.com/releases/2005/01/050121100142.htm

>In general, men have approximately 6.5 times the amount of gray matter related to general intelligence than women, and women have nearly 10 times the amount of white matter related to intelligence than men. Gray matter represents information processing centers in the brain, and white matter represents the networking of – or connections between – these processing centers.

These differences are only in a small portion of the brain statistically correlated with "g" in iq tests, not the entire cereberal cortex. If those sex differences were present in the whole cortex it would be the most obvious thing ever, we would have found out about it hundreds if not thousands of years ago.